Accumulated Other Comprehensive Loss - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Equity [Abstract]
Comprehensive income (loss)	$ 0	$ 13.6	$ 0	$ 13.6
Reclassified comprehensive (income) loss, Before tax	(0.1)	0.1	(0.2)	0.2
Other comprehensive loss Pension liability, tax (expense) benefit		$ (5.2)		$ (4.2)